OFFSET
9,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 9..413
FORMULA
a(n) ~ -(-1)^n * 2^(3*k) * Pi^(12*k) * exp(Pi*sqrt(3)*n) * n^(3*k - 1) / (3^(3*k) * Gamma(1/3)^(18*k) * Gamma(3*k)), set k = 9. - Vaclav Kotesovec, Mar 07 2018
MATHEMATICA
a[n_] := SeriesCoefficient[1/(1728*KleinInvariantJ[-Log[q]*I/(2*Pi)])^9, {q, 0, n}]; Table[a[n], {n, 9, 19}] (* Jean-François Alcover, Nov 02 2017 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Jul 07 2017
STATUS
approved